epoxy a carburetor float bowl?

[Sodo]

Who has experience with epoxy and (modern) gasoline? What kind of epoxy last years in a USA-gasoline environment?

I have 9HP Briggs & Stratton motor that has no float bowl drain. It has a very small boss cast into it, and perhaps feasible that it could be tapped for a small plug about 3/8". I don't have confidence that the sealing surface is good enough or would be square with regards to my tapped threads & I don't want it to seep. Also I want to use a larger cup-style plug. I'm thinking of cutting out the cup-style plug and boss from another carburetor and epoxy-ing it onto the bottom of this bowl. Alternatively, does anyone know if floatbowls are available for a B&S that already have a drain cup?

I like the "cup style" because it holds a sample of the stuff at the bottom. You can inspect for junk or water at the time of draining.

Here are pics of the floatbowl.

 

[paulwestski]

Just go for it drill and tap for a drain plug. Put a little bit of Teflon tape on the plug and you should be fine.

 

[hosspuller]

I would drip and tap the boss. Sealing washer & bolt would be better appearance and function wise.

 

[rsallen]

IF there's enough material for threads, drill and tap.
Smooth the boss down and use a rubber gasket or aluminum washer against a machined headed brass plug.

 

[/pine]

FWIW...I've seen "JB Weld" (epoxy) used on intake manifolds and it holds up well...

 

[pacerron]

Who has experience with epoxy and (modern) gasoline? What kind of epoxy last years in a USA-gasoline environment?

I have 9HP Briggs & Stratton motor that has no float bowl drain. It has a very small boss cast into it, and perhaps feasible that it could be tapped for a small plug about 3/8". I don't have confidence that the sealing surface is good enough or would be square with regards to my tapped threads & I don't want it to seep. Also I want to use a larger cup-style plug. I'm thinking of cutting out the cup-style plug and boss from another carburetor and epoxy-ing it onto the bottom of this bowl. Alternatively, does anyone know if floatbowls are available for a B&S that already have a drain cup?

I like the "cup style" because it holds a sample of the stuff at the bottom. You can inspect for junk or water at the time of draining.

Here are pics of the floatbowl.

]

Wouldn't it be a lot easier to just drop the bowl as you have here and dump it so you can see any scum/trash build up in the bottom of the bowl or on the float?

 

[Sodo]

Wouldn't it be a lot easier to just drop the bowl as you have here and dump it so you can see any scum/trash build up in the bottom of the bowl or on the float?

Not really, there is a flimsy & complex rubber gasket that you have to be sure to get back in all the right places and access & visibility isn't great. Basically, what happens is the eqpt gets "stored". After it's been there a few months; and winter is approaching, it's time to drain all the bowls in my multitude of gas engines (10 or more). By then, stuff (little motorcycles, trencher etc) is packed in tight around the mothballed eqpt. I decide that today is carb drain day and to get the bowls off I have to move all the other stuff, then move it all back. Everything else has drains and drain cups, want all to have drains.

JBWeld was my first thought, I've used it in many places but never immersed in gasoline.

I suppose Permatex Fuel Tank Repair might be more certain but is it a structural repair or just a 'plug'? I need it strong enough to resist wrench torque. Maybe seal it with the gas tank repair then cover it over with JBWeld?

Simplest is a brass 1/8 NPT, tap it and teflon, NPT is fine for once a year and a careful touch. Still considering that - but wrestling with the desire to look at whats in the bottom of the bowl at every draining. Then just the simple act of draining the carb can tell you a lot more.

Does anybody know what this is on the bottom of the bowl (of the pic below)? This bowl looks identical to mine but it apparently has threads? Is it a fuel shutoff for tipover? If the bowl is identical, I can buy this entire carb for $80 and just use the bowl.

 

[hosspuller]

Does anybody know what this is on the bottom of the bowl (of the pic below)? This bowl looks identical to mine but it apparently has threads? Is it a fuel shutoff for tipover? If the bowl is identical, I can buy this entire carb for $80 and just use the bowl.

Just a guess ... I have a Kohler engine with a similar do-hickey. It's an electric fuel shut-off. Prevents back-firing at shut down.

 

[jaotguy]

you can also use SEAL ALL ... gas , oil etc resistant.

 

[mikehaugen]

Maybe some type of solder?

Have you looked for a replacement bowl? Carbs get updated through the years and different manufactures have different requests etc, there's a good chance there was a version of the bowl that had the drain on some variation of engine.

 

[Sodo]

Yep Mike a couple posts above I investigated exactly that, the only way I could find one is to buy the whole carburetor.

If there was a solder for aluminum (that I could do, reliably) yes that would be a perfect solution. I bet there are ways, like in a sodium bath or some exotic process. I would certainly consider solder it if the bowl was steel.

Current plan is to add a nipple and construct a visible drain like this one (with clear tubing and a plug). Snowmobiles use this method. May be a challenge to get all of the water to fall down thru the fitting, the hole needs to be offset, and I'll fill the center with epoxy.

On my snowmobile the fuel tubing is 20 years old, clear & flexible. Does anybody know what kind of tubing stays clear and flexible for 20 years? It feels kind of like silicone, but a lot harder than silicone.

 

[jaotguy]

LUMI WELD sticks for soldering aluminum check out Eastwood catalog

 

[midnight rider]

Another thought would be to put a cheap fuel shut off valve inline before the carb and run the machine out of gas. Then no gas will sit in your bowl during the off season. Ethenol is horrible for pot metal carbs. I would be hesitent to drill into a bowlm which is probably pretty thin.

 

[tcartwri]

The bowl would be zinc, not aluminum. There is a zinc solder, but don't ask me where to find it.

 

[lostcause]

if you are going to drill it with a hand held drill then all bets are off and it's up to you to make it square, but if you have a drill press you can always tap holes perfectly square. just clamp the bowl down by the ears and drill the hole. then replace the drill with a tap (don't move the table or the bowl). use the downfeed lever on the drill press to hold pressure and turn the drill press chuck by hand, or use a rod in the chuck key hole for leverage if needed.

you only need to get a couple threads in and then you can remove the whole unit from the table (leave the tap threaded into the bowl) and then finish the threads with the a wrench. it will make good square threads by starting this way. i'd do that way before trying to start messing with soldering, epoxy, or any other sort of procedure. those are solutions for when it's already broken. then add a semi-soft gasket - fiber, rubber, o-ring, copper, or something similar.

 

[The Fred]

JB Weld is the answer if you need to repair a mess. I repaired many VW Rabbit carbs in the 80s where the float wore through the side of the carb. Never had one come back leaking the stuff is indestructible.

Fred

FAQs » JB Weld

 

[Sodo]

…..replace the drill with a tap (don't move the table or the bowl). use the downfeed lever on the drill press to hold pressure and turn the drill press chuck by hand

Thx Lostcause this worked PERFECT.

I also filed four drainways into the casting (with a rat-tail file) so if there's water it can go downhill and sit in the rubber tube not the carb bowl.

I'd like to find some clear flexible tubing for this fitting (with a plug).

 

[Soundguy]

LUMI WELD sticks for soldering aluminum check out Eastwood catalog

yep.. plenty of high zinc soldering soloutions for aluminum

 

[skyhook]

Could you not have put an 'O" ring on the inside of that, and then a nut to secure it.

 

[Sodo]

If there was a nut inside; then the bowl would have to fill with water to a level higher than the nut before it started to run out. The bowl could hold water then.

Intent for this modification is: If there's water or condensation in the carburetor bowl, it runs downward (out) into the tube; so I can see it in the clear tubing that extends below. And I can pull the plug and drain it easily, anytime.

The push-on fitting is threaded into the bowl with 1/8-28 NPT. While threading this, I kept stopping and checking it with the fitting, so I could control how far the (tapered thread) fitting extended into the bowl. I stopped when the fitting became 'flush' on the inside, and then "filed" 4 drains to ensure the water has a downward path out.